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    <title>Document</title>
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    <script>
        function fn() {
            var val;
            var newobj = Object.create({}, {
                name: {
                    value: "老李"
                },
                age: {
                    get: function () {
                        return val || 18;
                    },
                    set: function (a) {
                        val = a
                    }

                }

            })
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        var aa = new fn()
        console.log(aa)
        aa.age = 66
        console.log(aa)

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